The present invention relates to composite cables having combined optical and electrical power and/or transmission capabilities.
Conventional fiber optic cables include optical fibers that conduct light which is used to transmit voice, video, and data information. Conventional composite cables combine the advantages of optical transmission components, e.g., large bandwidth and low power loss, with the advantages of electronic/electrical transmission components which include low cost and straightforward termination procedures. Typical applications for composite cables include fiber-to-the-curb (FTTC), fiber-to-the-home (FTTH), fiber-to-the-desk (FTTD), plenum, riser, and local area networks (LANs). In a premises environment, composite cables can be used to interconnect hardware, for example, computers and telephones.
A conventional cable design is illustrative of transmission electrical cables. U.S. Pat. No. 5,681,179 discloses a conventional electrical zip cord with stranded electrical conductors only. The zip cord can be terminated with an electrical connector with relative ease, but the cable does not include optical transmission components.
Conventional composite cables can include a row of optical fibers and a separate row of electrical conductors. For example, U.S. Pat. No. 5,039,195 discloses a composite cable with two distinct cable units. A first cable unit includes optical fiber sub-units connected to strength members by a common jacket having interconnecting web sections. A second cable unit includes metal conductors connected by a common jacket having interconnecting web sections. Both cable units are surrounded by a cable jacket.
As disclosed in U.S. Pat. No. 5,602,953, a composite cable can include a combination of loose-buffered optical fibers and electrical conductors in a common jacket. The common jacket defines a flat structure including box-shaped sub-units, apparently formed by an injection molding process, with twisted electrical leads and optical fibers disposed in buffer tubes. The cable is designed to be separated into the box-shaped sub-units.
It is an object of the present invention to provide a composite cable unit having an optical sub-unit including at least one optical fiber, and an electrical sub-unit including at least one electrical conductor. The optical and electrical sub-units are removably connected together by a common jacket material.
It is an object of the present invention to provide a fan-out cable having a central member with cable units therearound. At least one of the cable units comprises a composite cable unit, the composite cable unit including an optical sub-unit with at least one optical fiber, and an electrical sub-unit including at least one electrical conductor, the optical and electrical sub-units being removably connected together by a common jacket material.